Bottle cap construction



Oct. 9, 1962 F. P. KROENERT 3,057,501

BOTTLE CAP CONSTRUCTION Filed Nov. 1e, 1960 f /5 Andrus Strke Tffforneys W FredRKrsLTz/:T

\ f' i .6. BY

United States Patent O ice 3,057,501 BOTTLE CAP CONSTRUCTION Fred P.Kroenert, Brookfield, Wis., assigner of one-half to Lore Kroenert,Brookfield, Wis. Filed Nov. 18, 1960, Ser. No. 70,264 8 Claims. (Cl.21S-39) This invention relates to a 'bottle cap construction and moreparticularly to a plastic insert for a metal bottle cap.

The conventional type of bottle cap structure includes an outer metalcap and a cork insert. In the sealing operation, the cork insert isforced against the upper edge of the bottle and the skirt or flange onthe metal cap is then crimped around the bead at the upper end of thebottle to clamp the cap to the bottle. The cork inserts which arecommonly used have several disadvantages in that the cork, being `a woodproduct, is subject to deterioration or decomposition after extendedperiods of shelf life. Furthermore, the cork, being porous, is oftencontaminated with other `foreign particles. For example, in theregistering operation in a bottle sealing process, great quantities ofbottle caps are dumped into a container and the caps are moved throughan aligning apparatus which aligns or registers the same for sealing. Inthe bulk container the sharp edges of the flanges of the caps oftenscrape olf the laquer on adjacent caps, and the lacquer particlespenetrate into the porous cork inserts and subsequently may contaminatethe material within the bottle. To eliminate these problems, the corkinserts, in many cases, have been lined with a metal foil, such asaluminum foil, which provides a smooth, nontoxic surface.

The present invention is directed to a plastic insert for a bottle capwhich is sanitary and nontoxic and provides a greater sealing action forthe bottle. The plastic insert can be used with either the standard typeof metal cap or other newly developed metal caps which operate on thelever arm principle to provide the sealing action.

More specifically, the plastic insert is disposed within the metal capand includes an annular flange which extends outwardly of the cap. Theouter peripheral surface of the ange is tapered and is adapted to bewedged within the opening in the bottle. In addition to the wedgesurface, an annular lip is provided on the insert which is spacedradially outward yfrom the flange. The lip is substantially smaller inaxial depth than the flange and is adapted to be engaged by the upperedge of the bottle and dellected inwardly to provide a secondary sealwith the bottle.

With the present insert, the internal pressure within the bottle acts toforce the annular flange radially outward into sealing engagement withthe inner surface of the neck of the bottle and the annular lip providesa second seal or corking action which further increases the sealingcharacteristics of the insert.

The plastic insert which is made out of a flexible plastic, such aspolyethylene, is nontoxic and sanitary and will not deteriorate orabsorb foreign matter.

As the insert includes the ange which is to be wedged within the openingof the bottle and also includes the annular lip which serves to providea corking action, the sealing effect of the plastic insert issubstantially greater than that of presently used inserts. Due to thisincreased sealing effect, a smaller force can be applied to the bottleat the time of sealing and therefore the bottles can be thinner and lesscostly. Furthermore, as the insert itself provides some holding actiondue to the wedging surface, a thinner metal cap can be used than in theconventional construction in which the cap itself provides the entireholding action.

Other objects and advantages will appear in 4the course of the followingdescription.

'3,057,501 Patented Oct. 9, 196.2

The drawings illustrate the ybest mode presently contemplated ofcarrying out the invention.

In the drawings:

FIGURE 1 is a transverse section showing the plastic insert of theinvention; I

FIG. 2 is a bottom elevation of the insert;

FIG. 3 is a transverse section showing the insert disposed within thecap prior to sealing;

FIG. 4 is a transverse section Ishowing the cap sealed on the bottle;

FIG. 5 is a transverse section showing the plastic insert disposedwithin a modified form of metal cap; and

FIG. 6 is a top view of the structure shown in FIG. 5.1'

The drawings illustrate a flexible plastic insert 1 which is disposedwithin a metal bottle cap 2 and is ad-apted to close olf or seal theopening in a bottle 3.

The insert 1 is 'adapted to be formed of a non-toxic, relativelyilexible plastic such a polyethylene, polyvinylcloride, polypropylene,or the like. However, any type of the common thermoplastic resins whichare non-toxic and will not react with, or be decomposed by, the contentsof the bottle can be used for the insert 1.

As best shown in FIG. l, the insert 1 includes a generally flat, centralbase portion 4 which is adapted to be disposed against the inner surface5 of the cap 2. An annular flange 6 extends axially from the base 4 andthe llange includes an inner wall 7 and a tapered outer wall 8 which isconnected to the inner wall 7. The outer Wall 8, being tapered, providesa wedge surface and is adapted to engage the inner surface of the neckof the bottle to provide a seal lfor the opening in the bottle. Theangle of taper A, as shown in FIG. 1, is in the range of 3 to 10 withabout 5 being preferred.

In addition to the flange 6, the insert 1 is also provided with anannular lip 9 which is disposed radially outward of the iiange 6. Asshown in FIG. 1, Ithe lip has a sturdy root portion yand has asubstantially smaller axial depth than the flange 6. In the sealingposition, the lip 9 is adapted to be engaged by the upper edge of thebottle 3 and is thereby deflected inwardly. The flexibility of theplastic serves to bias the lip outwardly into tight sealing engagementwith the bottle 3 and thereby provide a secondary seal or a corkingaction. If, for some reason, the internal pressure breaks the sealbetween the wedge surface 8 and the bottle 3, the secondary sealbetween' the lip 9 and the bottle will prevent leakage. I

The insert 1 is also provided with a generally at rim 10 which extendsradially outward from the lip 9, and terminates at the flange or skirt11`of the cap 2. As best seen in FIG. 1, the rim 10 is offset from theplane of the base 4. With this construction, when the insert is broughtinto contact with the upper edge of the bottle during the sealingaction, the force applied to the cap will be applied to the base 4,thereby serving to move the flange 6 outwardly into tight engagementwith the inner surface of the neck of the bottle. v

As best shown in lFIG. l, the inner Wall 7 is substantially thinner thanthe outer wall 8 and this enables the wall 7, which is subjected to theinternal pressure of the bottle in service, to be deflected outwardly bythe pressure and thereby increases the sealing effect of the outer wall8 with the bottle 3.

In the sealing operation, the insert 1 is initially assembled within thecap 2 and an adhesive can be employed if desired to bond the 'insert tothe inner surface 5 of the cap. The flange 11 of cap 2 is forced againstthe upper end of the bottle and the skirt 11 is bent inwardly andcrimped to provide a series of lips 12 which engage the lower edge ofthe bead 13 of the bottle to securely hold the cap to the bottle. Asbest shown in FIG. 4, the outer edge of the rim 10 is wrapped around theupper end of the bottle land this further increases the sealing effect.

FIGURES 5 and 6 illustrate the use of the plastic insert of theinvention with a modified form of a metal cap. As shown in thesefigures, the cap 14 is provided with a series of radial ribs 1S whichextend from the centerA of the upper surface 16 of the cap radiallyoutward and axially down along the skirt 17. The radial ribs serve aslever arms so that when pressure is applied to the center of the uppersurface 16, the ribs will tend to move the skirt outwardly to anexpanded posit-ion, and conversely, when the pressure is released, theskirt will move to a contracted position.

The cap 1'4 is applied to the bottle 3 in a manner similar to thatdescribed above, the skirt being crimped inwardly to engage the lowersurface of the bead 13 of the bottle.

The use of the tapered surface 8 in the plastic insert of the inventionserves to take up or compensate for any variance or irregularity in thediameter of the opening in the bottle and provides a tight wedging sealbetween the insert and the bottle. The internal pressure within thebottle acts against the thin inner wall 7 to dcform the same outwardlyand thereby increases the sealing effect with the bottle.

In addition to the sealing effect achieved by the tapered surface 8, asecondary seal is provided by the engagement of the deformable lip 9with the upper edge of the bottle. The resiliency of the plastic tendsto bias or urge the lip into tight sealing engagement with the bottle toprovide an auxiliary seal or corking action.

Due to the holding or sealing action of the insert itself, thinner metalcaps can be employed than in the conventional bottle caps in which thecork insert does not, in itself, provide any holding action. This canresult in a 20 to 30% decrease in the weight of steel required for thecap so that the bottle cap assembly using the plastic insert of theinvention is competitive pricewise with a cap construction utilizingfoil-covered cork inserts.

The insert of the invention can be used with all standard caps so thatthe existing facilities for producing the caps need not be changed whenemploying the present insert. The only change which may be required inexisting facilities is in the registering equipment in the sealingoperation.

Similarly, as the force applied to the cap is imparted at an anglethrough the wedge surface against the inner surface of the neck of thebottle and not directly against the top of the bottle, the bottles canlbe of thinner construction with a resulting saving in cost.

Various modes of carrying out the invention are contemplated as beingwithin the scope of the following claims particularly pointing out anddistinctly claiming the subject matter which is regarded as theinvention.

I claim:

1. An insert to be used for sealing an opening in a vessel, comprising acentral base section, an annular flange extending axially from the basesection and adapted to be received within the opening in the vessel,said flange having a peripheral surface progressively decreasing inexternal diameter in a direction away from the base section, saidperipheral surface adapted to wedgingly engage the inner surface of thevessel bordering the opening, and a generally resilient deformable lipdisposed radially outward of the flange and having an axial depthsubstantially less than said flange, said lip adapted to be engaged bythe upper edge of the vessel bordering the opening therein and to bedeformed radially inwardly, with the resiliency of said lip urging saidlip into tight sealing engagement with the upper edge of the vessel toprovide a secondary seal.

2. The structure of claim l, and including a generally flat rimextending radially outward from the lip and lying in a plane offsetaxially from the plane of the base section.

3. An insert to be used with a bottle cap for sealing the opening in abottle, comprising a central ybase section, a flexible generallycylindrical inner wall extending axially outward from said base section,a flexible annular outer wall connected to the outer portion of saidcylindrical Wall and diverging radially outward in a direction axiallyinward toward the plane of the base section, said walls adapted to beinserted within the opening of the bottle and said outer wall adapted towedgingly engage the neck of the bottle to seal the opening, a generallyflat rim connected to the axially inward portion of said outer wall, anda flexible annular lip connected to said rim at a location adjacent saidouter wall and having an axial length substantially less than the axiallength of said outer wall, said lip adapted to be engaged by the upperedge of the bottle bordering the opening therein and to he deformedradially inwardly, with the resiliency of said lip urging said lip intotight sealing engagement with the upper edge of the bottle to provide asecondary seal.

4. The structure of claim 3, in which the outer wall diverges outwardlyat an angle of 3 to 10 to the axis of the -insert and has asubstantially greater thickness than the inner Wall to permit the innerwall to be deformed radially outwardly by the internal pressure in thebottle and thereby increase the sealing effect of the outer wall withthe neck of the bottle.

5. A flexible plastic insert to be used with a bottle cap for sealingthe opening in a bottle, comprising a generally flat base sectionadapted to be disposed generally flatwise within the cap, a generallycylindrical inner wall extending axially outward from said base section,a flexible annular outer wall connected to the outer portion of saidcylindrical wall and diverging radially outward in a direction axiallyinward toward the plane of the base section, said walls adapted to beinserted with the opening of the bottle and said outer wall adapted towedgingly engage the neck of the bottle to seal the opening, a generallyflat rim connected to the axially inward portion of said outer Wall, andan annular lip connected to said rim at a location adjacent said outerwall and having an axial length substantially less than the axial lengthof said outer Wall, said lip being generally tapered and having Iagreater thickness at the `root than at the outer extremity thereof, saidlip adapted to be engaged by the upper edge of the bottle bordering theopening therein and to be deformed radially inwardly, with theresiliency of said lip urging said lip into tight sealing engagementwith the upper edge of the bottle to provide a secondary seal.

6. A bottle cap assembly, comprising a cap having a central portion anda peripheral skirt extending outwardly from the central portion andadapted to `be clamped to the outer surface of the neck of a bottle;`and a flexible plastic insert having a base section disposed generallyflatwise to the inner surface of the central portion of the cap andhaving an annular flange extending axially from the base section withsaid flange including an outer peripheral surface adapted to wedginglyengage the inner surface of the neck of the `bottle bordering theopening therein to seal the same, and said insert having an annulardeformable lip disposed radially outward of the flange and adapted toengage the upper edge of the bottle and to be deformed thereby, said liphaving an axial depth substantially less than said flange and adapted tobe disposed in tight sealing engagement with the upper edge of thebottle to provide a secondary seal for the opening.

7. A -bottle cap assembly, comprising a cap having a central portion anda peripheral skirt extending outwardly from the central portion andadapted to be clamped to the outer surface of the neck of a bottle; anda llexible plastic insert having a base section disposed generallyflatwise to the inner surface of the central portion of the cap, aflexible generally cylindrical inner wall extending axially outward fromsaid base section, a flexible annular outer wall connected to the outerportion of said cylindrical wall and diverging radially outward in adirection axially inward toward the plane of the base section, saidWalls adapted to be inserted Within the opening of the bottle and saidouter wall adapted to wedgingly engage the neck of the bottle to sealthe opening,

a generally flat rim connected to the axially inward portion of saidouter wall, and a flexible annular lip connected to said rim at alocation adjacent said outer wall and having an axial lengthsubstantially less than the axial length of said outer wall, said lipadapted to be engaged by the upper edge of the bottle bordering theopening therein and to be deformed radially inwardly, with theresiliency of said lip urging said lip into tight sealing engagementwith the upper edge of the bottle to provide a secondary seal.

8. An insert to be employed for sealing an opening in an article,comprising a generally ilat base section, an annular flange extendingaxially outwardly from the base section and having a peripheral surfaceprogressively decreasing in external diameter in a direction away fromsaid base section, said peripheral surface adapted to wedgingly engagethe inner surface of the article bordering the opening therein to sealthe same, and an annular deformable lip disposed radially outward of theange and adapted to engage the upper edge of the article bordering theopening and to be deformed thereby, said lip extending axially of thebase section with the axially outward extremity of said lip terminatingshort of the axially outward extremity of said flange and being separateand spaced from said flange, said lip adapted to be disposed in tightsealing engagement lwith the upper edge of the article to provide asecondary seal for the opening.

References Cited in the ile of this patent FOREIGN PATENTS 498,700 ItalySept. 30, 1954 :UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTIONPatent No. 3,057 501 October 9 1962 Fred P. Kroenert ppears in the abovenumbered vpat-- It is hereby certified that error a id Letters Patentshould read as ent requiring correction and that the sa corrected below.

Column 4, line 32, for "with" read within signed and sealed this 26thday of March 1963@ SEAL) Attest:

ESTON G. JOHNSON D AVID L. LADD';

Commissioner of Patents Attesting Officer

